Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 296 insertions, 0 deletions

diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h
new file mode 100644
index 00000000000..802c91e9b3d
--- /dev/null
+++ b/include/linux/buffer_head.h
@@ -0,0 +1,296 @@
+/*
+ * include/linux/buffer_head.h
+ *
+ * Everything to do with buffer_heads.
+ */
+
+#ifndef _LINUX_BUFFER_HEAD_H
+#define _LINUX_BUFFER_HEAD_H
+
+#include <linux/types.h>
+#include <linux/fs.h>
+#include <linux/linkage.h>
+#include <linux/pagemap.h>
+#include <linux/wait.h>
+#include <asm/atomic.h>
+
+enum bh_state_bits {
+	BH_Uptodate,	/* Contains valid data */
+	BH_Dirty,	/* Is dirty */
+	BH_Lock,	/* Is locked */
+	BH_Req,		/* Has been submitted for I/O */
+
+	BH_Mapped,	/* Has a disk mapping */
+	BH_New,		/* Disk mapping was newly created by get_block */
+	BH_Async_Read,	/* Is under end_buffer_async_read I/O */
+	BH_Async_Write,	/* Is under end_buffer_async_write I/O */
+	BH_Delay,	/* Buffer is not yet allocated on disk */
+	BH_Boundary,	/* Block is followed by a discontiguity */
+	BH_Write_EIO,	/* I/O error on write */
+	BH_Ordered,	/* ordered write */
+	BH_Eopnotsupp,	/* operation not supported (barrier) */
+
+	BH_PrivateStart,/* not a state bit, but the first bit available
+			 * for private allocation by other entities
+			 */
+};
+
+#define MAX_BUF_PER_PAGE (PAGE_CACHE_SIZE / 512)
+
+struct page;
+struct buffer_head;
+struct address_space;
+typedef void (bh_end_io_t)(struct buffer_head *bh, int uptodate);
+
+/*
+ * Keep related fields in common cachelines.  The most commonly accessed
+ * field (b_state) goes at the start so the compiler does not generate
+ * indexed addressing for it.
+ */
+struct buffer_head {
+	/* First cache line: */
+	unsigned long b_state;		/* buffer state bitmap (see above) */
+	struct buffer_head *b_this_page;/* circular list of page's buffers */
+	struct page *b_page;		/* the page this bh is mapped to */
+	atomic_t b_count;		/* users using this block */
+	u32 b_size;			/* block size */
+
+	sector_t b_blocknr;		/* block number */
+	char *b_data;			/* pointer to data block */
+
+	struct block_device *b_bdev;
+	bh_end_io_t *b_end_io;		/* I/O completion */
+ 	void *b_private;		/* reserved for b_end_io */
+	struct list_head b_assoc_buffers; /* associated with another mapping */
+};
+
+/*
+ * macro tricks to expand the set_buffer_foo(), clear_buffer_foo()
+ * and buffer_foo() functions.
+ */
+#define BUFFER_FNS(bit, name)						\
+static inline void set_buffer_##name(struct buffer_head *bh)		\
+{									\
+	set_bit(BH_##bit, &(bh)->b_state);				\
+}									\
+static inline void clear_buffer_##name(struct buffer_head *bh)		\
+{									\
+	clear_bit(BH_##bit, &(bh)->b_state);				\
+}									\
+static inline int buffer_##name(const struct buffer_head *bh)		\
+{									\
+	return test_bit(BH_##bit, &(bh)->b_state);			\
+}
+
+/*
+ * test_set_buffer_foo() and test_clear_buffer_foo()
+ */
+#define TAS_BUFFER_FNS(bit, name)					\
+static inline int test_set_buffer_##name(struct buffer_head *bh)	\
+{									\
+	return test_and_set_bit(BH_##bit, &(bh)->b_state);		\
+}									\
+static inline int test_clear_buffer_##name(struct buffer_head *bh)	\
+{									\
+	return test_and_clear_bit(BH_##bit, &(bh)->b_state);		\
+}									\
+
+/*
+ * Emit the buffer bitops functions.   Note that there are also functions
+ * of the form "mark_buffer_foo()".  These are higher-level functions which
+ * do something in addition to setting a b_state bit.
+ */
+BUFFER_FNS(Uptodate, uptodate)
+BUFFER_FNS(Dirty, dirty)
+TAS_BUFFER_FNS(Dirty, dirty)
+BUFFER_FNS(Lock, locked)
+TAS_BUFFER_FNS(Lock, locked)
+BUFFER_FNS(Req, req)
+TAS_BUFFER_FNS(Req, req)
+BUFFER_FNS(Mapped, mapped)
+BUFFER_FNS(New, new)
+BUFFER_FNS(Async_Read, async_read)
+BUFFER_FNS(Async_Write, async_write)
+BUFFER_FNS(Delay, delay)
+BUFFER_FNS(Boundary, boundary)
+BUFFER_FNS(Write_EIO, write_io_error)
+BUFFER_FNS(Ordered, ordered)
+BUFFER_FNS(Eopnotsupp, eopnotsupp)
+
+#define bh_offset(bh)		((unsigned long)(bh)->b_data & ~PAGE_MASK)
+#define touch_buffer(bh)	mark_page_accessed(bh->b_page)
+
+/* If we *know* page->private refers to buffer_heads */
+#define page_buffers(page)					\
+	({							\
+		BUG_ON(!PagePrivate(page));		\
+		((struct buffer_head *)(page)->private);	\
+	})
+#define page_has_buffers(page)	PagePrivate(page)
+
+/*
+ * Declarations
+ */
+
+void FASTCALL(mark_buffer_dirty(struct buffer_head *bh));
+void init_buffer(struct buffer_head *, bh_end_io_t *, void *);
+void set_bh_page(struct buffer_head *bh,
+		struct page *page, unsigned long offset);
+int try_to_free_buffers(struct page *);
+struct buffer_head *alloc_page_buffers(struct page *page, unsigned long size,
+		int retry);
+void create_empty_buffers(struct page *, unsigned long,
+			unsigned long b_state);
+void end_buffer_read_sync(struct buffer_head *bh, int uptodate);
+void end_buffer_write_sync(struct buffer_head *bh, int uptodate);
+void end_buffer_async_write(struct buffer_head *bh, int uptodate);
+
+/* Things to do with buffers at mapping->private_list */
+void mark_buffer_dirty_inode(struct buffer_head *bh, struct inode *inode);
+int inode_has_buffers(struct inode *);
+void invalidate_inode_buffers(struct inode *);
+int remove_inode_buffers(struct inode *inode);
+int sync_mapping_buffers(struct address_space *mapping);
+void unmap_underlying_metadata(struct block_device *bdev, sector_t block);
+
+void mark_buffer_async_write(struct buffer_head *bh);
+void invalidate_bdev(struct block_device *, int);
+int sync_blockdev(struct block_device *bdev);
+void __wait_on_buffer(struct buffer_head *);
+wait_queue_head_t *bh_waitq_head(struct buffer_head *bh);
+int fsync_bdev(struct block_device *);
+struct super_block *freeze_bdev(struct block_device *);
+void thaw_bdev(struct block_device *, struct super_block *);
+int fsync_super(struct super_block *);
+int fsync_no_super(struct block_device *);
+struct buffer_head *__find_get_block(struct block_device *, sector_t, int);
+struct buffer_head * __getblk(struct block_device *, sector_t, int);
+void __brelse(struct buffer_head *);
+void __bforget(struct buffer_head *);
+void __breadahead(struct block_device *, sector_t block, int size);
+struct buffer_head *__bread(struct block_device *, sector_t block, int size);
+struct buffer_head *alloc_buffer_head(unsigned int __nocast gfp_flags);
+void free_buffer_head(struct buffer_head * bh);
+void FASTCALL(unlock_buffer(struct buffer_head *bh));
+void FASTCALL(__lock_buffer(struct buffer_head *bh));
+void ll_rw_block(int, int, struct buffer_head * bh[]);
+int sync_dirty_buffer(struct buffer_head *bh);
+int submit_bh(int, struct buffer_head *);
+void write_boundary_block(struct block_device *bdev,
+			sector_t bblock, unsigned blocksize);
+
+extern int buffer_heads_over_limit;
+
+/*
+ * Generic address_space_operations implementations for buffer_head-backed
+ * address_spaces.
+ */
+int try_to_release_page(struct page * page, int gfp_mask);
+int block_invalidatepage(struct page *page, unsigned long offset);
+int block_write_full_page(struct page *page, get_block_t *get_block,
+				struct writeback_control *wbc);
+int block_read_full_page(struct page*, get_block_t*);
+int block_prepare_write(struct page*, unsigned, unsigned, get_block_t*);
+int cont_prepare_write(struct page*, unsigned, unsigned, get_block_t*,
+				loff_t *);
+int generic_cont_expand(struct inode *inode, loff_t size) ;
+int block_commit_write(struct page *page, unsigned from, unsigned to);
+int block_sync_page(struct page *);
+sector_t generic_block_bmap(struct address_space *, sector_t, get_block_t *);
+int generic_commit_write(struct file *, struct page *, unsigned, unsigned);
+int block_truncate_page(struct address_space *, loff_t, get_block_t *);
+int file_fsync(struct file *, struct dentry *, int);
+int nobh_prepare_write(struct page*, unsigned, unsigned, get_block_t*);
+int nobh_commit_write(struct file *, struct page *, unsigned, unsigned);
+int nobh_truncate_page(struct address_space *, loff_t);
+int nobh_writepage(struct page *page, get_block_t *get_block,
+                        struct writeback_control *wbc);
+
+
+/*
+ * inline definitions
+ */
+
+static inline void attach_page_buffers(struct page *page,
+		struct buffer_head *head)
+{
+	page_cache_get(page);
+	SetPagePrivate(page);
+	page->private = (unsigned long)head;
+}
+
+static inline void get_bh(struct buffer_head *bh)
+{
+        atomic_inc(&bh->b_count);
+}
+
+static inline void put_bh(struct buffer_head *bh)
+{
+        smp_mb__before_atomic_dec();
+        atomic_dec(&bh->b_count);
+}
+
+static inline void brelse(struct buffer_head *bh)
+{
+	if (bh)
+		__brelse(bh);
+}
+
+static inline void bforget(struct buffer_head *bh)
+{
+	if (bh)
+		__bforget(bh);
+}
+
+static inline struct buffer_head *
+sb_bread(struct super_block *sb, sector_t block)
+{
+	return __bread(sb->s_bdev, block, sb->s_blocksize);
+}
+
+static inline void
+sb_breadahead(struct super_block *sb, sector_t block)
+{
+	__breadahead(sb->s_bdev, block, sb->s_blocksize);
+}
+
+static inline struct buffer_head *
+sb_getblk(struct super_block *sb, sector_t block)
+{
+	return __getblk(sb->s_bdev, block, sb->s_blocksize);
+}
+
+static inline struct buffer_head *
+sb_find_get_block(struct super_block *sb, sector_t block)
+{
+	return __find_get_block(sb->s_bdev, block, sb->s_blocksize);
+}
+
+static inline void
+map_bh(struct buffer_head *bh, struct super_block *sb, sector_t block)
+{
+	set_buffer_mapped(bh);
+	bh->b_bdev = sb->s_bdev;
+	bh->b_blocknr = block;
+}
+
+/*
+ * Calling wait_on_buffer() for a zero-ref buffer is illegal, so we call into
+ * __wait_on_buffer() just to trip a debug check.  Because debug code in inline
+ * functions is bloaty.
+ */
+static inline void wait_on_buffer(struct buffer_head *bh)
+{
+	might_sleep();
+	if (buffer_locked(bh) || atomic_read(&bh->b_count) == 0)
+		__wait_on_buffer(bh);
+}
+
+static inline void lock_buffer(struct buffer_head *bh)
+{
+	might_sleep();
+	if (test_set_buffer_locked(bh))
+		__lock_buffer(bh);
+}
+
+#endif /* _LINUX_BUFFER_HEAD_H */